Variable fitting foam blocks as aggregate

Abstract

Specially-shaped blocks of foam for use underground as aggregate. Because of protuberances on the faces of the blocks, the blocks fit closely together in only a small number of ways. In filling a volume, the overwhelmingly more likely arrangements provide a reasonably certain percentage void. Thus, the blocks can be transported to an application arranged without any significant void, and then used to fill a volume, providing a reasonably well known percentage void and compressive strength. Use of these foam blocks can provide thermal insulation, cushioning and various combinations of compressive strength and void, depending on the size and shape of the blocks and the size and shape of the protuberances relative to the blocks.

What is claimed is: 
     
       1. A plurality of specially-shaped solid blocks for use underground as aggregate, the blocks having elongated protuberances and mating recesses on each face, the protuberances and mating recesses on a face all mutually parallel and also parallel to an edge of the face, the protuberances and mating recesses on each face oriented in one of a plurality of possible orientations, each solid block having at least two different orientations of protuberances and mating recesses in that if any one of the blocks is rotated about an axis through its center and parallel to an edge of a face so as to rotate into view different faces, the protuberances and mating recesses continue in one direction, and if the same block is then rotated about another axis perpendicular to the first axis and so as to again rotate into view different faces, the protuberances and mating recesses alternate in alignment by ninety degrees, thereby providing that the plurality of blocks fit closely together only when arranged in a small fraction of the number of ways the blocks can be arranged, and providing a pre-determined void in a volume when distributed throughout the volume with some minor disorder. 
     
     
       2. Specially-shaped blocks as claimed in claim 1, with N protuberances on one-half of the faces of each block and N+1 protuberances on the other half of the faces of each block. 
     
     
       3. A plurality of specially-shaped blocks as claimed in claim 1, wherein each block has two protuberances on one-half of its faces and three protuberances on the other half. 
     
     
       4. A plurality of specially-shaped blocks as claimed in claim 1, wherein the blocks are made of a material that is non-biodegradable. 
     
     
       5. A plurality of specially-shaped blocks as claimed in claim 1, wherein each block is made from expanded polystyrene. 
     
     
       6. A plurality of specially-shaped blocks as claimed in claim 5, wherein the material used to make the blocks has been recycled. 
     
     
       7. A plurality of specially-shaped blocks as claimed in claim 1, wherein the blocks are colored to indicate their use. 
     
     
       8. A plurality of specially-shaped solid blocks for use underground as aggregate, the blocks having elongated protuberances and mating recesses on each face, the protuberance and each mating recess lying substantially in a line, the protuberances and mating recesses on each face substantially mutually parallel, the protuberances and mating recesses on a face also all parallel to an edge of the face, each solid block having protuberances and mating recesses on two different faces aligned in two different directions in the that if any one of the blocks is rotated about an axis through its center and parallel to an edge of a face so as to rotate into view different faces, the protuberances and mating recesses continue in one direction, and if the same block is then rotated about another axis perpendicular to the first axis and so as to again rotate into view different faces, the protuberances and mating recesses alternate in alignment by ninety degrees, thereby providing that the plurality of blocks fit closely together only when arranged in a small fraction of the number of ways the blocks can be arranged, and providing a pre-determined void in a volume when distributed throughout the volume with some minor disorder.